Department of Meridian Research, Fujian Academy of Chinese Medical Sciences, Key Laboratory of Propagated Sensation Along Meridian of Fujian Province, Fuzhou 350003, China.
Zhen Ci Yan Jiu. 2024 Feb 25;49(2):155-163. doi: 10.13702/j.1000-0607.20220908.
To investigate the mechanism of electroacupuncture (EA) at "Neiguan" (PC6) in impro-ving myocardial electrical remodeling in rats with acute myocardial infarction (AMI) by enhancing transient outward potassium current.
A total of 30 male SD rats were randomly divided into control, model and EA groups, with 10 rats in each group. The AMI model was established by subcutaneous injection with isoprenaline (ISO, 85 mg/kg). EA was applied to left PC6 for 20 min, once daily for 5 days. Electrocardiogram (ECG) was recorded after treatment. TTC staining was used to observe myocardial necrosis. HE staining was used to observe the pathological morphology of myocardial tissue and measure the cross-sectional area of myocardium. Potassium ion-related genes in myocardial tissue were detected by RNA sequencing. The mRNA and protein expressions of Kchip2 and Kv4.2 in myocardial tissue were detected by real-time fluorescence quantitative PCR and Western blot, respectively.
Compared with the control group, cardiomyocyte cross-sectional area in the model group was significantly increased (<0.01), the ST segment was significantly elevated (<0.01), and QT, QTc, QTd and QTcd were all significantly increased (<0.05, <0.01). After EA treatment, cardiomyocyte cross-sectional area was significantly decreased (<0.01), the ST segment was significantly reduced (<0.01), and the QT, QTc, QTcd and QTd were significantly decreased (<0.01, <0.05). RNA sequencing results showed that a total of 20 potassium ion-related genes co-expressed by the 3 groups were identified. Among them, Kchip2 expression was up-regulated most notablely in the EA group. Compared with the control group, the mRNA and protein expressions of Kchip2 and Kv4.2 in the myocardial tissue of the model group were significantly decreased (<0.01, <0.05), while those were increased in the EA group (<0.01, <0.05).
EA may improve myocardial electrical remodeling in rats with myocardial infarction, which may be related to its functions in up-regulating the expressions of Kchip2 and Kv4.2.
通过增强瞬时外向钾电流，研究电针“内关”（PC6）改善急性心肌梗死（AMI）大鼠心肌电重构的机制。
将 30 只雄性 SD 大鼠随机分为对照组、模型组和电针组，每组 10 只。皮下注射异丙肾上腺素（ISO，85mg/kg）建立 AMI 模型。电针治疗，每日 1 次，每次 20min，共 5 天，治疗后记录心电图（ECG）。TTC 染色观察心肌坏死，HE 染色观察心肌组织病理形态，测量心肌横截面积。通过 RNA 测序检测心肌组织中钾离子相关基因。实时荧光定量 PCR 和 Western blot 分别检测心肌组织中 Kchip2 和 Kv4.2 的 mRNA 和蛋白表达。
与对照组相比，模型组心肌细胞横截面积显著增大（<0.01），ST 段明显抬高（<0.01），QT、QTc、QTd 和 QTcd 均显著升高（<0.05，<0.01）。电针治疗后，心肌细胞横截面积显著减小（<0.01），ST 段明显降低（<0.01），QT、QTc、QTcd 和 QTd 均显著降低（<0.01，<0.05）。RNA 测序结果显示，三组共鉴定出 20 个钾离子相关基因共表达。其中，电针组 Kchip2 表达上调最显著。与对照组相比，模型组心肌组织中 Kchip2 和 Kv4.2 的 mRNA 和蛋白表达均显著降低（<0.01，<0.05），而电针组则升高（<0.01，<0.05）。
电针可能通过上调 Kchip2 和 Kv4.2 的表达改善心肌梗死后大鼠的心肌电重构。
